There is increasing demand for wireless radio frequency (RF) communications to operate reliably under non-ideal conditions, for example, in lossy environments in which the material properties of the environment cause attenuation or dissipation of the RF signals. These lossy environments include, for example, mines, underground caves and tunnels, bore holes, subways, large buildings, under water, and so forth where signal quality can be severely compromised. Currently there is limited ability to maintain communications in such lossy environments, thereby prohibiting the quick and effective deployment of wireless systems in such environments.
Recent tragic events and mining emergencies have highlighted the need for a reliable communications system between miners trapped inside the mine and the outside. Wire-based communications systems can be ineffective because they may fail due to exposure to fires, roof falls, explosions tearing down wires, power failure, and/or the like. Unfortunately, however, underground environments, such as mines, pose a particularly unique and hostile environment for radio signals because radio communication systems require a clear path or open air for signal propagation. Thus, stoppings or roof falls halt or impede conventional signal propagation.
Accordingly, systems that achieve improved penetration distance in a lossy environment, while concurrently achieving reduced cost, size, and weight are needed so that wireless communication systems can be more extensively and usefully employed.